Glycosyltransferase activities in chicken brain synaptic junctions.
Isolated synaptic junction fractions from adult chicken brain were found to contain a number of glycoprotein glycosyltransferase with different donor and acceptor specificities. The activities of sialyl- and galactosyltransferases towards endogenous acceptors in the synaptic junction fraction were low but increased greatly after the addition of deglycosylated fetuin or mucin as exogenous acceptors. The activity of the fucosyltransferases towards endogenous acceptors in the fraction was much higher than that of the other transferases. The addition of deglycosylated fetuin caused a smaller increase in the activity than with the other transferases and deglycosylated mucin had no effect. We find no evidence for the enrichment of any glycosyltransferase in the synaptic junction. If anything, our results suggest that the synaptic junction may be specifically depleted in one type of fucosyltransferase.
D000818:Animals; D001921:Brain / Q000201:enzymology*; D002645:Chickens; D005647:Fucosyltransferases / Q000378:metabolism*; D005700:Galactosyltransferases / Q000378:metabolism*; D006602:Hexosyltransferases / Q000378:metabolism*; D007700:Kinetics; D012799:Sialyltransferases / Q000378:metabolism*; D013347:Subcellular Fractions / Q000201:enzymology; D013379:Substrate Specificity; D013569:Synapses / Q000201:enzymology*; D014166:Transferases / Q000378:metabolism*
D014166:Transferases; D005647:Fucosyltransferases; D005700:Galactosyltransferases; D006602:Hexosyltransferases; D012799:Sialyltransferases